Greatest Common Divisor
Detailed guide and Python implementation for the 'Greatest Common Divisor' problem.
Problem Statement
Write a function gcd(a, b) that takes two non-negative integers a and b (not both zero) and returns their Greatest Common Divisor (GCD) using the Euclidean algorithm. The GCD is the largest number that divides both a and b.
The Euclidean algorithm works by repeatedly replacing the larger number with the remainder of dividing the larger by the smaller, until the remainder is 0. The last non-zero remainder is the GCD.
- •0 <= a, b <= 10^6
- •a and b are not both zero
Examples
gcd(48, 18)
6
48 % 18 = 12, then 18 % 12 = 6, then 12 % 6 = 0. So GCD is 6.
gcd(56, 98)
14
98 % 56 = 42, 56 % 42 = 14, 42 % 14 = 0. So GCD is 14.
gcd(0, 5)
5
GCD(0, n) = n for any positive n.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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